Ballast tamping workhead

ABSTRACT

A ballast tamping workhead having tamping blades rigidly fixed to high-frequency vibratory motors that are carried, through compression-loaded insulating mountings, for up and down movement and swinging movement both toward the rail and toward the ties. Actuation of the workhead drives the vibrating blades into the ballast on either side of a tie, forces the blades in a squeezing action toward the rail, and then forces the blades in a further squeezing action toward and under the tie.

United States Patent [72] Inventor James E. Anderson Ludington, Mich.

[21] Appl. No. 855,579

[22] Filed Sept. 5, 1969 [45 Patented Dec. 7, 1971 [73] Assignee JacksonVibrators, Inc.

Ludington, Mich.

[54] BALLAST TAMPING WORKHEAD 6 Claims, 6 Drawing Figs.

[52] US Cl 104/12 [51] lnt.Cl E0lb27/l6 [50] Field otSearch 104/12, 7, 856] References Cited UNITED STATES PATENTS 2,734,463 2/1956 Hurshetal.

2,887,066 5/1959 Talboys 104/12 2,899,909 8/1959 Jackson 104/123,177,813 4/1965 Stewart 104/12 3,387,567 6/1968 Reynolds. 104/122,107,639 2/1938 Madison 104/12 Primary Examiner-Arthur L. La PointAssistant Examiner-Richard A. Bertsch Attorney-Wolfe, Hubbard, Leydig,Voit & Osann, Ltd.

ABSTRACT: A ballast tamping workhead having tamping blades rigidly fixedto high-frequency vibratory motors that are carried, throughcompression-loaded insulating I mountings, for up and down movement andswinging movement both toward the rail and toward the ties. Actuation ofthe workhead drives the vibrating blades into the ballast on either sideof a tie, forces the blades in a squeezing action toward the rail, andthen forces the blades in a further squeezing action toward and underthe tie.

PATENTEU um 7:91: 3625' 156 sum 1 OF 4 frmm zfli PATENTED DEC 7191:3.625; 156

saw 2 0F 4 BALLAST TAMPING WORKHEAD DESCRIPTION OF THE INVENTION Thisinvention relates to railroad ballast tamping machines and moreparticularly concerns a workhead for such machines.

Railroad rails are secured to crossties which, in turn, are set intoballast such as crushed rock or stone. ln building or maintaining atrack, the ballast must be positioned and compacted under the ties tohold the rails in proper position both horizontally and laterally. Themost critical ballast region is beneath the tie portions that liedirectly under the rails since this region bears the bulk of the trafficloads.

There have been two somewhat different approaches to tamping ballast.First, pressure has been used to force the ballast toward its properplace and degree of compaction. Second, high-frequency vibration hasbeen employed to agitate the ballast into tightly compacted, properlylocated regions. Some tamping machines have tried to combine the effectsof vibration with forcing or squeezing the ballast into position, butthe design considerations for each approach have not been compatible andprior tamping machines have been primarily of one type or the other.

It is the primary aim of the present invention to provide a tampingworkhead that combines true high-frequency vibration tamping witheffective and forceful squeeze-type tampmg.

Another object of the invention is to provide a tamping workhead of theabove character which positively and directly acts on the criticalballast region beneath the tie portions under the rails. Stated anotherway, not only is high-frequency vibration imparted to the ballast beingtamped, but a squeezing action is developed both from opposite sides andtoward the tie, and from opposite sides and toward the rail.

A further object is to provide a tamping workhead as characterized abovewhich is well suited for the rough, heavyduty use to which suchequipment is normally subject.

Other objects and advantages of the invention will become apparent uponreading the following detailed description and upon reference to thedrawings, in which:

FIG. 1 is a side elevation of a portion of a tamper embodying theinvention;

FIG. 2 is an enlarged fragmentary elevation taken approximately alongthe line 2-2 of FIG. 1;

FIG. 3 is an enlarged side elevation of a portion of the structure shownin FIG. 1 with the parts in a different operating position;

FIG. 4 is an enlarged fragmentary section taken along the line 4-4 inFIG. 3;

FIG. 5 is a diagrammatic plan showing the movement of the tamper bladesin the tamper of the invention; and

FIG. 6 is a simplified hydraulic diagram showing the actuating circuitsfor the structure of FIG. 1.

While the invention will be described in connection with a preferredembodiment, it will be understood that I do not intend to limit theinvention to that embodiment. On the contrary, I intend to cover allalternatives, modifications and equivalents as may be included withinthe spirit and scope of the invention.

Turning first to FIG. 1, there is shown a portion of a tamper 10 havinga frame 11 adapted to move along a railroad track 12. The track 12includes a pair of rails 13, only one of which is shown, mounted on aplurality of crossties 14 placed in ballast 15. In the illustratedconstruction, the tamper l0 rides on flanged wheels 16 which arejournaled on the frame 11 for guiding the tamper along the track 12.

Those familiar with this art will understand that tamping involvesplacing and compacting the particles making up the ballast under theties 14 and, for this purpose, the tamper includes a pair of workheads,of which only the workhead 20 over the rail 13 is illustrated. It willbe understood that, preferably, a similar workhead is mounted on thetamper 10 over the opposite rail which does not appear in the drawings.

A pair of generally vertical guides in the form of rods 21 are fixed tothe tamper frame 11 longitudinally of the track 13, and the workhead 20includes a crosshead 22 mounted on the rods 21 for vertical slidingmovement above the rail 13. In more detail, the crosshead 22 is formedby generally square sideplates 23 sandwiching bearing sleeve assemblies24 at their four corners which slide on the rods 21. A pair of boxlikearms 25 are fixed to the sideplates 23 and extend laterally of the rail13 from either side of the rods 21.

For moving the crosshead 22 up and down, a double-acting hydraulicactuator 26 is anchored at 27 to the frame 11 between the guide rods 21with the end of its piston rod being secured at 28 to cars 29 extendingupwardly from the crosshead sideplates 23.Extending the actuator 26raises the crosshead 22, and contracting the actuator drives thecrosshead downwardly. A hook 30 (see FIG. 1) is pivoted on the frame 11to engage a pin on the crosshead to lock the crosshead in raisedposition for transport.

In accordance with the invention, the crosshead 22 carries fourhigh-speed vibratory motors 35 mounting blades 36 which, when tamping,are moved down into the ballast 15, in toward and under the rail 13, andthen squeezing toward and under the tie 14. Diagrammatically, the blades36 move along the paths 37 shown in FIG. 5.

The crosshead actuator 26 moves the blades 36 into and out of theballast 15. For moving the blades toward and under the rail 13, a pairof depending supports 41 are pivoted on axes 42 on the crosshead arms 25for swinging movement down and toward the rail 13. Each support 41includes a short beam 43 and pairs of depending plates 44. A pair ofdouble-acting hydraulic actuators 45 are anchored to the crosshead withtheir piston rods connected to respective ones of the supports 41 so asto hold the supports in this FIG. 2 position and to also swing thesupports along the arcs 46, thus carrying the blades 36 toward and underthe rail 13.

For moving the blades 36 toward and under the ties 14, two pairs ofmotor carriers 50 are mounted on the crosshead 22 with one pair beingpivoted on a common axis 51, at the lower end of each of the dependingsupport plates 44, for swinging movement down and toward opposite sidesof a tie 14. Each motor carrier 50 is controlled by a double-actinghydraulic actuator 52 connected between the support beam 43 and therespective carriers 50.

The motor carriers 50 are formed as boxlike frames containing thevibratory motors 35. The motors are electrically powered and arepositioned with their rotors paralleling the ties l4 and havingeccentrics at each rotor end so that forceful, high-frequencyoscillatory vibration preferably on the order of 4,500 v.p.m. is createdparallel to the rail 13.

To insulate this vibration from the other parts of the workhead 20 whilemaintaining directional control of the blades 36, compression-loadedmounting assemblies 53 secure each motor 36 at its four corners withinits respective carrier 50. Each assembly 53 sandwiches a pair ofmounting lugs 54 secured to the carrier 50 between upper and lower motormounting plates 55 and 56, respectively. A bolt 57 surrounded by steelsleeves 58 with an intermediate washer 59 runs between the motormounting plates 53 and through holes in the lugs 54 so that drawing thebolt 57 tightly locks the plates 55, 56, sleeves 58 and washer 59rigidly. A pair of elastic T- shaped grommets 61 are fitted over thesleeves 58 with their heads between the plates 55, 56 and the adjacentone of the lugs 54. Drawing the bolt 57 tight flares out the shank endsof the grommets 61 between the washer 59 and the adjacent lugs 54 (seeFIG. 4). The result is a compression-loaded vibration absorbing assembly53 which still allows movement of the carrier 50 to control movement ofthe motor 35 and the attached blades 36.

As a feature of the invention, two blades 36 are fixed to each motor 35through a bracket 65, with the blades 36 having flat, working ends orpads 66 mounted on shanks 67 with V- shaped cross sections, and the fourblade working ends 66 closest to the rail 13 are angled so as to face,in a horizontal plane, the intersection of the rail and tie (see H6. 5).In this way, the tamping work is done by the working ends or pads 66with the V-shaped shanks 67 simply cutting through the ballast 15, andthe working ends 66 compact the ballast in the most important regionsunder the tie and, in particular, under that portion of the tie beneaththe rail 13.

ln describing the control and sequencing of the workhead actuators 26,45 and 52, a circuit will be described in connection with FIG. 6 whichincludes corresponding actuators 26', 45' and 52' for performingcorresponding functions with a workhead, not illustrated, which operatesover the opposite rail. The workheads may be operated independently ofeach other, and in describing the controls for the workhead 20, thecorresponding parts for the opposite workhead will be given the samereference numeral with a prime mark added.

The tamper operator institutes a tamping cycle by energizingelectrically controlled three-way valves 71 and 71' so that, when thevalves shift downwardly as shown schematically, fluid pressure isdirected from a supply 72 to the ends of the actuators 26, 26' thatcause them to contract. This drives the crossheads including thecrosshead 22 downwardly. Pressure relief valves 73 and 73' control theamount of down pressure available to the actuators 26, 26'. When thevalves 73, 73' open at their set pressures, fluid is returned directlyfrom the supply 72 to a return line 74.

In carrying out the invention, sequence valves 75 and 75' send fluidunder pressure to the actuators 45, 45' after a predetermined amount ofpressure is developed in the actuators 26, 26'. In this way, the blades36 are first driven down into the ballast and then, at a down pressuredetermined by the setting of the valves 75, 75 the actuators 45 areenergized to tilt the supports 41 and drive the blades 36 toward andunder the rail 13. An overload valve 76 and a pair of check valves 77are provided in the circuit as safety factors.

Once the blades 36 are fully into the ballast, a fact determined by amagnet 78 on the crosshead 22 coming into alignment with a magneticswitch 79 on the frame 11 (see FIGS. 1 and 3), the actuators 52, 52' arebrought into play by the switch 79 controlling a two-way valve 81 thatdirects fluid to the actuators 52. A similar valve 81' controls theactuators 52'. Energizing the valve 81 causes the actuators 52 to drivethe blades 36 in a squeezing action toward and under a tie 14.

As a feature of the invention, the actuators 52, 52 receive fluid underpressure from accumulators 82 and 82, respectively, which are keptcharged by piloted valves 83 and 83'. The piloted valves 83, 83"deliverhydraulic fluid to the actuators 82, 82' until their set pressure isreached, whereupon fluid is bypassed from the supply 72 through a line84 to the return line 74. In this way, through the use of theaccumulators 82, 82', the tamping blade squeezing action is quick andpowerful, and is not directly dependent upon the supply of fluid fromthe line 72.

The squeezing action of the blades 36 under a tie 14 is limited byhydraulic pressure sensitive switches 85 and 85 which, when the operatorset pressure is reached, open the circuits to the solenoids controllingthe valves 81, 81 and thus allow these valves to be restored and theactuators 52, 52' to return to their initial positions. The amount ofsqueezing pressure exerted by the blades 36 is thus controlled bysetting the switches 85, 85, which can be done by the tamper operator.

The tamper operator, by controlling the three-way valves 71, 71' canmake repeated tamping insertions of the blades 36 into the ballast 15and then raise the workhead for movement over the next tie 14. With eachinsertion, the sequential action bringing the actuators 45, 45' and thenthe actuators 52 and 52 into operation is repeated.

It can therefore be seen that the workhead 20 effectively combines truehigh-frequency vibration tamping with effective and forcefulsqueeze-type tamping. This has been attained in a rugged structure wellsuited for heavy-duty, production use on railroad track. The blades 36are mounted and moved in a fashion which insures proper tamping not onlybeneath the ties but also beneath that critical portion of the tie thatunderlies the track rails.

I claim as my invention:

1. In a tamper having a frame adapted to move along a railroad trackincluding a rail mounted on crossties placed in ballast, a tampingworkhead comprising, in combination, generally vertical guides mountedon said frame, a crosshead mounted on said guides for generally verticalmovement above said rail, a pair of depending supports pivoted on saidcrosshead for swinging movement down and toward said rail, two pairs ofmotor carriers with one pair being pivoted at the lower end of each ofsaid supports for swinging movement down and toward opposite sides ofone of said ties, four highspeed vibratory motors mounted one on each ofsaid motor carriers so as to produce oscillatory vibration parallel tosaid rail, blades affixed to each of said motors, means for moving saidcrosshead down so as to drive said blades into the ballast on eitherside of a tie, means for positively swinging both of said supports so asto tilt said blades under pressure toward and under the rail, and meansfor positively swinging all four of said carriers so as to move theblades under pressure toward and under said tie.

2. The combination of claim 1 in which two blades are fixed to eachmotor with the blades having flat working ends aligned generallyparallel to the ties, the four blade working ends that are closest tothe rail being angled so as to face, in a horizontal plane, theintersection of said rail and said tie.

3. The combination of claim 2 in which said blade working ends aresupported by shanks having a V-shaped horizontal section with the pointsof the V facing the tie toward and under which the blade ends move.

4. The combination of claim 1 in which said motor carriers are boxlikeframes containing said motors, the combination including a plurality ofresilient, compression loaded mounting assemblies securing each motorwithin its carrier so as to isolate motor vibration while maintainingdirectional control of said blades.

5. The combination of claim 1 in which said last three means arehydraulic actuators, the combination including a control circuit forsaid actuators causing said supports to be swung after the buildup of apredetermined pressure in the actuator moving the crosshead down, andsaid circuit also causing said carriers to be swung after the workheadreaches a predetermined lowered position.

6. The combination of claim 5 in which said circuit includesaccumulators for giving a fast surge of power to the actuators swingingsaid carriers, and said circuit also including a settable pressureresponsive switch for stopping the swinging movement of said carriersafter a predetermined pressure has been exerted by the blades on theballast.

a a c 4:

1. In a tamper having a frame adapted to move along a railroad trackincluding a rail mounted on crossties placed in ballast, a tampingworkhead comprising, in combination, generally vertical guides mountedon said frame, a crosshead mounted on said guides for generally verticalmovement above said rail, a pair of depending supports pivoted on saidcrosshead for swinging movement down and toward said rail, two pairs ofmotor carriers with one pair being pivoted at the lower end of each ofsaid supports for swinging movement down and toward opposite sides ofone of said ties, four high-speed vibratory motors mounted one on eachof said motor carriers so as to produce oscillatory vibration parallelto said rail, blades affixed to each of said motors, means for movingsaid crosshead down so as to drive said blades into the ballast oneither side of a tie, means for positively swinging both of saidsupports so as to tilt said blades under pressure toward and under therail, and means for positively swinging all four of said carriers so asto move the blades under pressure toward and under said tie.
 2. Thecombination of claim 1 in which two blades are fixed to each motor withthe blades having flat working ends aligned generally parallel to theties, the four blade working ends that are closest to the rail beingangled so as to face, in a horizontal plane, the intersection of saidrail and said tie.
 3. The combination of claim 2 in which said bladeworking ends are supported by shanks having a V-shaped horizontalsection with the points of the V facing the tie toward and under whichthe blade ends move.
 4. The combination of claim 1 in which said motorcarriers are boxlike frames containing said motors, the combinationincluding a plurality of resilient, compression loaded mountingassemblies securing each motor within its carrier so as to isolate motorvibration while maintaining directional control of said blades.
 5. Thecombination of claim 1 in which said last three means are hydraulicactuators, the combination including a control circuit for saidactuators causing said supports to be swung after the buildup of apredetermined pressure in the actuator moving the crosshead down, andsaid circuit also causing said carriers to be swung after the workheadreaches a predetermined lowered position.
 6. The combination of claim 5in which said circuit includes accumulators for giving a fast surge ofpower to the actuators swinging said carriers, and said circuit alsoincluding a settable pressure responsive switch for stopping theswinging movement of said carriers after a predetermined pressure hasbeen exerted by the blades on the ballast.